require 'digest/sha1'
class User < ActiveRecord::Base
  has_many :conversations, :dependent => :protect
  has_many :user_roles, :dependent => :destroy
  has_many :roles, :through => :user_roles
  belongs_to :employee
  
  # Virtual attribute for the unencrypted password
  attr_accessor :password
  attr_accessor :role_ids
  
  after_save :update_roles
  
  validates_presence_of     :login, :email
  validates_presence_of     :password,                   :if => :password_required?
  validates_presence_of     :password_confirmation,      :if => :password_required?
  validates_length_of       :password, :within => 4..40, :if => :password_required?
  validates_confirmation_of :password,                   :if => :password_required?
  validates_length_of       :login,    :within => 2..40
  validates_length_of       :email,    :within => 3..100
  validates_uniqueness_of   :login, :email, :case_sensitive => false
  before_save :encrypt_password
  
  # prevents a user from submitting a crafted form that bypasses activation
  # anything else you want your user to change should be added here.
  attr_accessible :login, :email, :password, :password_confirmation, :role_ids, :employee_id
  
  # Authenticates a user by their login name and unencrypted password.  Returns the user or nil.
  def self.authenticate(login, password)
    u = find_by_login(login) # need to get the salt
    u && u.enabled? && u.authenticated?(password) ? u : nil
  end
  
  # Encrypts some data with the salt.
  def self.encrypt(password, salt)
    Digest::SHA1.hexdigest("--#{salt}--#{password}--")
  end
  
  # Encrypts the password with the user salt
  def encrypt(password)
    self.class.encrypt(password, salt)
  end
  
  def authenticated?(password)
    crypted_password == encrypt(password)
  end
  
  def remember_token?
    remember_token_expires_at && Time.now.utc < remember_token_expires_at 
  end
  
  # These create and unset the fields required for remembering users between browser closes
  def remember_me
    remember_me_for 2.weeks
  end
  
  def remember_me_for(time)
    remember_me_until time.from_now.utc
  end
  
  def remember_me_until(time)
    self.remember_token_expires_at = time
    self.remember_token            = encrypt("#{email}--#{remember_token_expires_at}")
    save(false)
  end
  
  def forget_me
    self.remember_token_expires_at = nil
    self.remember_token            = nil
    save(false)
  end
  
  def update_roles
    unless role_ids.nil?
      self.user_roles.each do |user_role|
        user_role.destroy unless role_ids.include?(user_role.role_id.to_s)
        role_ids.delete(user_role.role_id.to_s)
      end 
      role_ids.each do |role_id|
        self.user_roles.create(:role_id => role_id) unless role_id.blank?
      end
      reload
    end
  end
  
  protected
  # before filter 
  def encrypt_password
    return if password.blank?
    self.salt = Digest::SHA1.hexdigest("--#{Time.now.to_s}--#{login}--") if new_record?
    self.crypted_password = encrypt(password)
  end
  
  def password_required?
    crypted_password.blank? || !password.blank?
  end
  
  
  
end
